I just bought flysky th9x from rcbazzar....
need suggestions regarding battery..
Can I use lithium ion 18650 size battery in it
if yes how many should i use and please tell me any local shop from where i can buy these........

thank you...

Harsh,

I am not sure if you can use "lithium ion 18650 size battery" in your Tx.

As far as I know you have 2 options:

1. go for 8 AA batteries (rechargeable are better and cost effective )
2. go for Tx Lipo pack like this http://hobbysea.com/products.php?5&cPath=4&sid=0067ffa30da05934d3e412d2fe4bb7e5

Second would be better and serve you well in long run. I have the the same Tx Rx and recently I bought the above LiPo pack.

I have seen a 1400mAh 3S LiPo being used and I use it on my HK 6Ch. It works fine.

i am using Life 9.9v works great for me!
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=14076
and using Frsky module

Wat battery should be used for the Turnigy 9x? Tried 4AA size eveready batteries n it didn't switch on.

You've a couple of choices:

1. LiFePO4 -9.9v (as suggested by praveen, i am using the same. serves about 8-10 flights easily on a full charge)

2. LiPo 3S -11.1 v - 1C discharge - similar to 1 but my Radio module would heat up a little perhaps because of higher voltage.

3. Rechargeable AA batteries (NiMH/NiCd) - 1.2v - You will need 8 cells to power it (did it not come with a 8 cell battery holder?) - these are cost effective - as correctly advised by Amit

4. Normal AA sized batteries - You will need 8 again. Go for anything from eveready to panasonic or Duracell. Eveready will last about 3-4 flights,  Duracell about 12-15, maintaining a good range - turn out to be quite expensive in the long run

5. You can use 18650 but you will either have to do a hardware mod or if th9x allows, you can set the low voltage alarm. I know er9x does but unsure about th9x. You can get 18650s from dealextreme.com but it will take a while to reach and I can understand the excitement. You will need 2 * 18650 batteries

I am quite happy with the LiFe battery, they last long but your charger should support charging LiFe's. Do NOT charge with a balanced LiPo charger, it will swell. @praveen - do you use a LiFe charger to charge these, because mine swell and i wouldn't recommend using LiPo voltages to charge. Do share your experiences...

yes boss! i am using it past from 8 months no issue ! i use turnigy charger ,but charging in life mode (it has got 3 type of battery option li-po,li-fe and l-ion)! no swelling or heating or drop in voltage! i am getting more than 15 flights per charge !even more.
Which charger you are using to charge life batteries?

I am using the Accucell 6 now. Works well on the LiFe mode...

Originally charged once on LiPo balance charger and screwed it..hehe, which is why being very careful in recommending.

Great, yes it should last over 15 flights, mine goes down because I am on the simulator as well ...sorry, forgot to mention that.

I don't think as I can insert 8AA size batteries in it.It can hold only 4AA.

This is how the stock connector looks like, with a lead coming out of it for connection. Four AAs go on one side and four on another.

However, I am surprised to know that it didnt even turn on with eveready AA * 4 (6v) because the radio runs on 5v regulated. I hope you used brand new batteries and the polarity was correct...It should have turned on at 6v and beeped.

better go for life batteries. Lipo is not so safe. You need to be careful with it.

Check this out,

http://www.rcindia.org/index.php?topic=9772.0

Using 4 batteries would not complete the circuit for current flow since the holder is meant for 8 batteries in series. Current and voltage input to radio with 4 batteries would be 0V and 0A

Here are a couple of pictures showing different types of batteries which are used in Radio Txs which are designed to take 8AA size cells.

1. Best option:  Li-FE 9.9 Volt Transmitter battery.
2. Second option : 8 cell 9.6 volt Ni-Cd / Ni-MH Tx batterypack.
3. Last option:  8 AA size Duracell batteries in a battery holder that came with the Tx.

NOTE: I charge my Tx batteries outside of the Tx using appropriate fast charger instead of keeping the battery pack inside the Tx and using the regular over night charger. I use a Delta Peak Detection charger to fast charge my Ni-Cd/Ni-MH battery packs and the popular B6 multi chemistry charger in Li-FE mode to charge my Li-FE , Tx battery pack at the recommended charge current rate.

After charging the battery pack and inserting it in the Tx and connecting the battery lead to its connector inside the Tx take extra care to connect the right way. If you connect in Reverse Polarity the Tx will get seriously damaged.   

Very correct. However, xxxkrishxxx in his reply no 8 indicates confidently that the battery holder can *only hold 4 batteries* (he does correct himself in a later post though), reason I confirm for the type of the holder in the next post...

I didn't look the back side of the holder